Many solutions for securing inter-provider handover proposed to date make use of the concept of security context transfer. However, none of these solutions addresses problems arising from subsequent handover. In this paper, we provide a formal model for subsequent security context transfer and define a set of security requirements. We furthermore present a new solution that meets all but one of these requirements. In particular, we combine the concept of a history-enriched security context transfer with a policy-based handover decision process.